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2002-10-15 | SCIENCE
Studying Evolution with Digital Organisms

Using a software program named Avida, researchers at the California Institute of Technology and Michigan State University are using "digital organisms" to study the workings of Darwinian evolution. These digital creatures exist only as a string of computer code that is initially written by their human designers. As the organisms vie with each other for processor space, they're allowed to mutate and evolve; only the strongest competitors survive. Studying this digital fight for survival is providing insight into evolution in real-life situations. For instance, the scientists have found that high rates of reproduction don't guarantee the upper hand. Organisms that reproduce quickly tend to be more successful when mutation rates are low. But when mutation rates are high, it's actually the more robust organisms (those able to mutate without incapacitating themselves) that win out, even if they reproduce more slowly. These virtual organisms may also aid in the search for life on other planets by helping to identify the biosignatures (evidence of life) of organisms based on different chemisty than that of Earth life. Understanding the evolution of life on the molecular, organism, and ecosystem levels can tell us a great deal about the development of life on Earth as well as other planets. Uncovering ecological principles such as the dynamics of competition between species can also yield valuable information about how ecosystems respond to environmental change, a primary goal of astrobiology.

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Full text of original item from Astrobiology Magazine, Oct 15, 2002

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